-54C Pour Point and high PAO content

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I've never really noticed any significant difference in how my engine runs with different brands of oil but I believe those that do notice it. People eem to say that often about SSO.
 
SSO or ASM gives me the best engine smoothness when idling and at take off. It also doesn't cause ticking on cold-startup in the winter. Mobil 1 was very close to this, but not 100% the same so I just stuck with Amsoil.

In the summer I will run Pennzoil Platinum because it's cheaper and gives me the same results as the Amsoil in feeling and on the UOA in warmer weather but in the cooler weather it ticks like Dino.
 
Originally Posted By: Art_Vandelay
Let me clarify:

- I mean exactly -54C. Not -53, -65, -48 etc.


There is no magic in the number -54°C. The flash point procedure (ASTM D-92) calls for passing the flame every 5°F or 3°C. If you run the test with a Centigrade thermometer you will check for a flash in 3°C increments, so you can get -51, -54, -57 etc. If you run it with a Farenheit thermometer you check every 5°F, so you can get -60, -65, -70 etc. If you run it in Farenheit and convert to Centigrade, -65°F exactly equals -54°C.

Tom NJ
 
What does flash procedure have to do with PP?

here's M1 10w-40 racing current PDS:


Mobil 1
Racing 4T
Product Number 48138-2
Engine/Application Type 4-Cycle
SAE Grade 10W-40 20W-50
Service Classification API SJ,SH, SG/CF
Density, lb/gal @ 60°F 7.28
Flash Point (ASTM D92), °C (°F) 253 (487)
Pour Point, °C (°F) -54 (-65)
Viscosity
Kinematic, cSt @ 40°C 86.0
Kinematic, cSt @ 100°C 13.8
Cold Cranking, cP 2900 @ -20°C
Pumping, cP 11500 @ -30°C
Viscosity Index 164
 
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Originally Posted By: Tom NJ
There is no magic in the number -54°C. The flash point procedure (ASTM D-92) calls for passing the flame every 5°F or 3°C. If you run the test with a Centigrade thermometer you will check for a flash in 3°C increments, so you can get -51, -54, -57 etc. If you run it with a Farenheit thermometer you check every 5°F, so you can get -60, -65, -70 etc. If you run it in Farenheit and convert to Centigrade, -65°F exactly equals -54°C.

Tom NJ


That explains the -54 versus other close numbers, but is there a reason why -54 is apparently so common amongst synthetics?
 
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Originally Posted By: Canawler
That explains the -54 versus other close numbers, but is there a reason why -54 is apparently so common amongst synthetics?


Not really. The pour point is influenced by the additives and VII as well as the base oils, so it can fall anywhere. Plus the test method is +- 3C.

Tom NJ
 
Originally Posted By: Tom NJ
Originally Posted By: Canawler
That explains the -54 versus other close numbers, but is there a reason why -54 is apparently so common amongst synthetics?


The pour point is influenced by the additives and VII as well as the base oils, so it can fall anywhere.

Tom NJ


Tom,

In 1996 wouldn't Mobil 1 have been a Group IV oil?
 
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I was just going to add there is nothing magical (about knowing the base content) and a -54°C PP.

I could add solvent to a nasty thick oil and make it pour at -54°C. It would not mean it's PAO.
 
Originally Posted By: Pablo
I was just going to add there is nothing magical (about knowing the base content) and a -54°C PP.

I could add solvent to a nasty thick oil and make it pour at -54°C. It would not mean it's PAO.
But would it have a flash of 250C+?
 
Originally Posted By: ARCOgraphite
Originally Posted By: Pablo
I was just going to add there is nothing magical (about knowing the base content) and a -54°C PP.

I could add solvent to a nasty thick oil and make it pour at -54°C. It would not mean it's PAO.
But would it have a flash of 250C+?

No, that would be what's called a dumb-bell blend (high and low viscosities mixed) and the flashpoint would be low due to it being more influenced by the flashpoint of the lower viscosity fluid.
 
If you look at the specs on PAO base oil the 2, 4, 5 and 6 cSt base oils range -66 to -54 C. 8 and 10 cSt PAO have pour points of -48 C. Esters also have pour points in this range.

Chevron's UCBO (high viscosity index group III) base oils in 4 and 7 cSt blends have pour points of -18 C. These are base fluids with nearly as high of viscosity index as PAO, at 127 and 135. The pour point for Shell XHVI is also listed at -18, so I would imagine it takes pour point depressant/wax inhibitors and blending to make them pour at -40 or lower temperatures.

I would say a pour point below -48 C is usually a sign of high PAO or ester content, maybe not specifically a -54 pour point but a pour point below -48 would point that direction.
 
Mobil 1 15W-50(1996) has a pour point of -54C. Lower than their newest 5W-20 which is only -47C.


Do any of you really think that XOM engineered 15W-50 to have a lower pour point here? I think it's pretty clear it's characteristic of the base oil?

When your synthetic base oil is, just say around 80% Group IV(PAO), then it's going to have an intrinsically low pour point.

When your synthetic base oil is, say around 80% Group III(hydrocracked), then it's going to have an intrinsically higher pour point in comparison.

Does anyone not agree with that?

Mobil 1 15W-50 (1996 Formula)

http://cakymsds.com/images/pdf/msd55281.pdf

Mobil 1 5W-20 (current)

http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil_1_5W-20.asp
 
But realistically, how many BITOGers start their engine in -50 degree weather. Now for industrial equipment operating in Canada, Maine and Alaska it might be a real issue. The difference between -30 and -54 might have real world consequences.
 
A 5W-30 that pours at -54 versus a 5W-30 that pours at -30 means that the oil that pours at -54 probably performs as good at -15 as the oil that pours at -30 does above freezing.

It does make a difference.

Good enough isn't good enough.
 
According to the current MSDS for M1 5w30, pour point is now only -33F.

However, PAO is supposedly still in very short supply. Many suppliers are reformulating on the fly, partially substituting Grp III and then boosting the AO to offset. Not sure if things are back to normal now. I would assume they are. I have heard though that now is an bad time to make a long-term opinion of an oil's quality based on what's currently out there.

Grp III could also be part of future M1 oils. Who knows...

Companies like Amsoil/Redline don't sell enough oil to really be impacted by the supply shortage. They don't move anywhere near the volume XOM does.
 
Has anyone else noticed that the pour point listed on most oils product data sheet's and the pour point listed on the msds are different. Actually every oil I've looked at is this way. Does anyone else find this disturbing?
 
Shouldn't I be MORE concerned about CCS vis than PP for cold startability? (and, yes, I know the village is 'subtly' hinting about grp-iii invading the beloved synthetics)
 
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